Antenna arrays including waveguide antenna elements are becoming an important communication tool because they provide desirable antenna gain and beamforming properties for communication over long distances. Passive antenna arrays with waveguide feed networks are one of the most suited technologies for antenna arrays because of the low level of losses they exhibit.
A traditional limitation with waveguide antenna elements is operational bandwidth range. For example, waveguides typically have a lower cutoff frequency that is dependent on the dimensions of the waveguide, and an operational range that is a fraction of an octave starting at a frequency above the lower cutoff frequency. However, various applications may call for a wider operational bandwidth. For example, it may be desirable to support frequencies in portions of the Ku-band, K-band, and Ka-bands, which range from 12 GHz to 40 GHz. Additionally, a communication system may be configured for transmission and reception over two different frequency ranges, which may be discontinuous. Current antenna arrays using waveguide antenna elements have bandwidth limitations that reduce their capabilities or ability to communicate with various satellite systems.